With normal mobile phones fast becoming "so yesterday", nearly half of all New Zealand households now have a smartphone.

OPERATING SYSTEMS

The brains of your device, managing your phone's hardware and software and dictating the usability of your phone and the apps you can download.

APPLE

Apple's iOS has led the way in making smartphones easy and attractive to use ever since the debut of the iPhone and many would agree it is still tops for usability. When it comes to apps, iOS is also still No 1, with more than 700,000 apps to choose from.

ANDROID

Google's Android is the most popular, because there are a multitude of handsets (at a range of prices) from different manufacturers running it.

Google doesn't tightly control which manufacturers use Android or what features they include in their handsets - which makes for some cutting-edge phones but some inconsistency across Android devices.

Android integrates well with Google's range of online services, Gmail, Maps, Calendar, Talk, etc. Google's app store Google Play has just ticked over 700,000 apps, closing in on Apple.

WINDOWS PHONE 8

Microsoft's latest version of its mobile operating system debuted this week and Windows Phone 8 smartphones should be appearing in shops shortly.

It displays your most-used apps such as Hotmail as live or updated tiles on your home screen, so you can see at a glance all the latest activity. The range of apps is still relatively limited but should improve over time. And, of course, there's smooth integration with Outlook and Microsoft Office.

BLACKBERRY

BlackBerry's star has faded big time with the arrival of the iPhone and Android smartphones, but it's still an appealing choice for some businesspeople. Advantages are long battery life, secure emailing, and - for some - a physical keyboard. But on the downside there are very few apps, and the hardware, with a low-res, non-touchscreen, means you won't be getting a true smartphone experience.

SPECS

❏ Touchscreens: The most visible and for many the most important spec.

Touchscreen resolution is often expressed in pixel dimensions, such as the Samsung Galaxy S3's 1280 x 720 - this basically means the screen has 1280 pixels (units of colour) along the length of the screen and 720 pixels along the width. Other manufacturers express resolution as pixel density - the iPhone 5 has smaller pixel dimensions but a pixel density of 326 pixels an inch (306ppi for the Samsung Galaxy S3). For a phone with good screen resolution, go for at least 800 x 400 pixels, and if you want razor-sharp resolution, look for the highest pixel density count.

❏ Battery life: You'll probably find you need to charge your smartphone a lot more than you did your old, more basic mobile because it's doing so much more.

Most of the time battery life is described in milliampere hours (mAh) to give an idea of how long the device will run for before the battery needs recharging.

Generally the higher the mAh number the better the battery life, but this also depends on the phone, and devices with bigger screens will use more power. Higher end smartphones today have more than 1400mAh of battery life.

❏ Processor power: Processors are the brawn that enable smartphones to carry out all the tasks you ask of them, such as surfing the web, playing games and watching video.

Processor power is measured in Gigahertz - the higher the number the better - and the number of cores a processor has - dual-core processors are better at multitasking than their single-core counterparts, and quad-core processors are another step up altogether. Aim for a processor of at least 1GHz and two cores.

Other specs to consider:

❏ Camera - smartphone cameras are typically pretty sharp these days. Again, bigger is better when it comes to megapixels but between 2MP and 8MP is usually adequate.

❏ Memory - for photos and video you will need a bit of memory. Today's smartphones pack between 1GB and 32GB, and many also let you expand memory with a micro SD card.

PROVIDERS AND PLANS

Most smartphone users are on a monthly post-paid plan, which gives them a certain number of minutes and texts and a mobile broadband allowance.

There are myriad plans available and one size does not fit all, so think carefully about your usage before opting for a plan. Consumer NZ's TelMe website is a handy tool in this regard.

Traditionally Telecom plans have offered more data, Vodafone is more generous with its text allowances and 2degrees has cheaper calling and text rates but smaller data bundles.

Consumer NZ says Telecom deals are currently the most attractive, with more data, lots of texts and good pre-pay plans.

Before choosing a provider, make sure it has 3G coverage including mobile broadband coverage in your area - you can find coverage maps on providers' websites and through the TelMe site. 2degrees is still building its network and uses Vodafone's where it doesn't have coverage.

It has mobile broadband zones and customers must use other data packs or pay different data rates.